Air conditioner

ABSTRACT

Even in the case of a large outdoor heat exchanger ( 24 ), it is possible to completely remove frost without reducing the defrosting effect. Provided are: a distributor ( 25 ) installed between the outdoor heat exchanger ( 24 ) and an expansion valve ( 26 ); a plurality of distribution pipes ( 252 ) of which one end is connected to the distributor ( 25 ) and of which the other end is connected to a plurality of heat transfer pipes ( 241 ) of the outdoor heat exchanger ( 24 ); and a bypass pipe ( 30 ) of which one end is connected to a compressor ( 23 ) and diverges on the way, and simultaneously of which the respective plurality of other ends are connected to a connection part between the distribution pipe ( 252 ) and the heat transfer pipe ( 241 ) or in the vicinity thereof.

TECHNICAL FIELD

The present disclosure relates to an air conditioner having a defrosting function.

BACKGROUND ART

A conventional air conditioner is configured to remove frost by supplying a high temperature gas refrigerant discharged from a compressor to an outdoor heat exchanger while continuing heating.

As disclosed in Japanese Unexamined Patent Application Publication No. 2009-85484, specifically, a conventional air conditioner is provided with a compressor, an outdoor heat exchanger, and an expansion valve, as well as a bypass pipe that is installed for connecting a pipe of a discharge port of an indoor heat exchanger and a pipe which connects the outdoor heat exchanger and the expansion valve. The present disclosure provides a defrosting function enabled by supplying a high temperature gas refrigerant from a compressor to a heat transfer pipe of an outdoor heat exchanger through the bypass pipe during defrosting.

By the way, an increasing length of heat transfer pipe is needed with the outdoor heat exchanger becoming bigger, and accordingly, pressure loss becomes bigger due to flow path resistance. Here, when a big outdoor heat exchanger is generally used, a plurality of heat transfer pipes are separated from each other, a distributor is installed between an outdoor heat exchanger and an expansion valve, and simultaneously the distributor and each of the heat transfer pipes are connected by a distribution pipe.

However, when defrosting such a big outdoor heat exchanger, since a high temperature gas refrigerant flows from the compressor into the distribution pipe and is supplied to each of the heat transfer pipes, an amount of flow of the high temperature gas refrigerant decreases due to the flow path resistance of the distribution pipe. Accordingly, there is a problem in a big outdoor heat exchanger of residual frost due to insufficient removal of the frost resulting from increased defrosting time caused by the degradation of defrosting performance.

DISCLOSURE Technical Problem

The present disclosure is directed to providing an air conditioner which completely remove frost without decreasing a defrosting effect even in a big outdoor heat exchanger

Technical Solution

One aspect of the present disclosure provides an air conditioner which includes a refrigerant circuit in which a compressor, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger are connected, and further includes a distributor provided between the outdoor heat exchanger and the expansion valve, a plurality of distribution pipes connected to a plurality of heat transfer pipes in which each one end thereof is connected to the distributor and the other end thereof is included in the outdoor heat exchanger, and a bypass pipe having one end connected to the compressor, and configured to branch off in the middle thereof, and each of a plurality of the other ends is connected to connection portion of the distribution pipe and the heat transfer pipe or nearby.

In the case of the air conditioner, since each of the other ends of the bypass pipe is connected to the connection portion of the distribution pipe and the heat transfer pipe or nearby, a high temperature gas refrigerant may be supplied to the heat transfer pipe almost without flow path resistance of the distribution pipe. Accordingly, even in the case of a big outdoor heat exchanger, frost may be significantly removed without a decrease in an amount of high temperature gas refrigerant and also a degradation of a defrosting effect.

It may be preferable that the air conditioner further includes auxiliary distributors to which a plurality of heat transfer pipes are connected, one ends of the distribution pipes be respectively connected to the plurality of heat transfer pipes through the auxiliary distributors, and the other ends of the bypass pipe be respectively connected to the auxiliary distributors.

Thus, as the other ends of bypass pipe are respectively connected to the auxiliary distributors, the number of branches of the bypass pipe may be decreased, and a cost reduction or a weight reduction may be obtained.

As a specific embodiment, the outdoor heat exchanger may be installed in plural, and the distributor, the distribution pipe, and the bypass pipe may be installed to correspond to each of the outdoor heat exchangers.

In addition, it may be preferable that the outdoor heat exchanger includes a plurality of heat exchange units and further includes a defrosting controller which individually defrosts the heat exchange units and switches the heat exchange unit to be defrosted, and the defrosting controller starts to defrost one heat exchange unit and starts to defrost another heat exchange unit before ending defrosting of the one heat exchange unit.

In the case of the air conditioner, since the defrosting controller starts to defrost one heat exchange unit and starts to defrost another heat exchange unit before ending defrosting of the one heat exchange unit, water generated in the defrosted heat exchange unit is prevented from freezing in another heat exchange unit, and the heat exchange units may be confidently defrosted while continuing heating operation.

It may be preferable that the plurality of heat exchange units be vertically installed and the defrosting controller sequentially switches the heat exchange unit to be defrosted from the heat exchange unit positioned at an upper side to the heat exchange unit positioned at a lower side

Thus, water generated by defrosting the upper side heat exchange unit may be more confidently prevented from freezing in the lower side heat exchange unit.

It may be preferable that the outdoor heat exchanger includes an upper heat exchange unit, a middle heat exchange unit, and a lower heat exchange unit, and a capacity of the middle heat exchange unit be smaller than that of each of the upper heat exchange unit and the lower heat exchange unit.

Thus, since the capacity of the middle heat exchange unit is small, the temperature of the middle heat exchange unit may easily become high, and water generated by defrosting the upper heat exchange unit may be further confidently prevented from freezing in the middle heat exchange unit.

In addition, since the capacity of the middle heat exchange unit is small, an amount of water generated by defrosting the middle heat exchange unit may be small, and it may be difficult for frost to be generated in the lower heat exchange unit. As a result, defrosting time of the lower heat exchange unit may be decreased.

It may be preferable that the defrosting controller simultaneously defrosts the upper heat exchange unit and the middle heat exchange unit, switches the heat exchange unit to be defrosted from the upper heat exchange unit to the lower heat exchange unit, and simultaneously defrosts the middle heat exchange unit and the lower heat exchange unit.

Thus, water generated by defrosting the upper heat exchange unit may be further confidently prevented from freezing in the middle heat exchange unit and the heat exchange units may be confidently defrosted.

It may be preferable that the defrosting controller defrosts the middle heat exchange unit between start and end of defrosting of the upper heat exchange unit and simultaneously defrosts the middle heat exchange unit between start and end of defrosting of the lower heat exchange unit.

It may be preferable that the air conditioner further includes a heat storage tank which stores heat of the compressor, simultaneously heats a refrigerant with heat stored in the heat storage tank and causes the refrigerant to flow to the outdoor heat exchanger through the bypass pipe.

Thus, the air conditioner may heat a refrigerant using heat radiated from the compressor, and a high efficiency defrosting operation may be obtained. Accordingly, a degradation of heating performance during a defrosting operation may be prevented, and a user's comfort during the defrosting operation may be maintained.

It may be preferable that a refrigerant which flows from the heat storage tank flow into the outdoor heat exchanger through the bypass pipe, after being introduced into the compressor.

Thus, the refrigerant which flows from the heat storage tank becomes an even higher temperature in the compressor, and the defrosting time may be decreased.

Thus, residual ice generated between the upper heat exchange unit and the middle heat exchange unit or residual ice generated between the lower heat exchange unit and the middle heat exchange unit may be confidently prevented.

Advantageous Effects

A refrigerator according to an exemplary embodiment of the present disclosure can completely remove frost without decreasing a defrosting effect even in a big outdoor heat exchanger.

DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic block diagram of an air conditioner of a first embodiment.

FIG. 2 is a schematic block diagram of a heat transfer pipe and a distribution pipe connection portion of the first embodiment.

FIG. 3 is a schematic block diagram illustrating a modified example of the air conditioner of the first embodiment.

FIG. 4 is a schematic block diagram of an air conditioner of a second embodiment.

FIG. 5 is a view for describing a defrosting operation of the second embodiment.

FIG. 6 is a schematic block diagram illustrating a modified example of the air conditioner of the second embodiment.

FIG. 7 is a view for describing a defrosting operation of the modified example of the second embodiment.

FIG. 8 is a schematic block diagram of a configuration of a bypass pipe of the modified example of the second embodiment.

FIG. 9 is a schematic block diagram of the air conditioner of the modified example of the second embodiment.

MODES OF THE INVENTION First Embodiment

Hereinafter, an air conditioner of a first embodiment of the present disclosure will be described in detail with reference to accompanying drawings. In addition, numerals in the first embodiment will only be used in FIGS. 1 to 3.

As illustrated in FIG. 1, an air conditioner 100 according to the embodiment of the present disclosure includes an indoor unit 10 and an outdoor unit 20 and has a heat pump cycle 200 formed so that a refrigerant flows in the indoor unit 10 and the outdoor unit 20.

Depressurizing units 11A and 11B connected in parallel, indoor heat exchangers 12A and 12B respectively connected to the depressurizing units 11A and 11B, and indoor blower fans 13A and 13B are installed in the indoor unit 10.

A four way valve 21, an accumulator 22, a compressor 23, an outdoor heat exchanger 24, a distributor 25, an expansion valve 26, and an outdoor blower fan 27 are installed in the outdoor unit 20.

The heat pump cycle 200 is provided with a main circuit 201 in which the depressurizing units 11A and 11B, the indoor heat exchangers 12A and 12B, the four way valve 21, the outdoor heat exchanger 24, the distributor 25, and the expansion valve 26 are sequentially connected and a compression circuit 202 in which the accumulator 22 and the compressor 23 are sequentially connected and connected to the four way valve 21.

By controlling opening and closing of the four ports of the four way valve 21, the heat pump cycle 200 may be provided to reverse the flow of the refrigerant in the main circuit 201 and to switch between a cooling operation and a heating operation. Specifically, during the cooling operation, the four way valve 21 is provided to introduce a high temperature gas refrigerant discharged from the compressor 23 to the outdoor heat exchanger 24, and during a heating operation, the four way valve 21 is provided to introduce a high temperature gas refrigerant discharged from the compressor 23 to the indoor heat exchangers 12A and 12B.

Here, as illustrated in FIGS. 1 and 2, a plurality of auxiliary distributors 251 and a plurality of distribution pipes 252 are installed between the outdoor heat exchanger 24 and the distributor 25 in the embodiment of the present disclosure.

The auxiliary distributor 251 is disposed near the outdoor heat exchanger 24 and simultaneously connected with a plurality of heat transfer pipes 241 included in the corresponding outdoor heat exchanger 24. Although three auxiliary distributors 251 are installed and each of the auxiliary distributors 251 are connected to three heat transfer pipes 241 in FIG. 1, the number of auxiliary distributors 251 and the number of heat transfer pipes 241 connected to the auxiliary distributors 251 are not limited to the above-described numbers.

The distribution pipe 252 connects the distributor 25 and the outdoor heat exchanger 24 and, by simultaneously distributing a refrigerant flowing from the distributor 25 to the outdoor heat exchanger 24, supplies the refrigerant to each of the heat transfer pipes 241. More specifically, one end of the distribution pipe 252 is connected to the distributor 25, and the other end is connected to the auxiliary distributor 251 and simultaneously connected to the heat transfer pipe 241 through the auxiliary distributor 251.

That is, the distribution pipe 252 and the heat transfer pipe 241 are connected to each other through the auxiliary distributor 251 interposed therebetween.

In addition, as illustrated in FIGS. 1 and 2, a bypass pipe 30 is installed in the air conditioner 100 according to the embodiment of the present disclosure, wherein one end of the bypass pipe 30 is connected to a discharging side pipe 231 of the compressor 23, the bypass pipe 30 is branched from the middle thereof, and simultaneously a plurality of the other ends thereof are connected to connection portions of the distribution pipes 252 and the heat transfer pipes 241 or to nearby. In the embodiment of the present disclosure, as described above, the auxiliary distributor 251 is interposed between the distribution pipe 252 and the heat transfer pipe 241 (referred to as the connection portion), and the other ends of the bypass pipe 30 are respectively connected to the auxiliary distributors 251.

Specifically, the bypass pipe 30 includes a main pipe 31 connected to the discharging side pipe 231 of the compressor 23 and a plurality of branch pipes 32 branched from intersection points P installed on the main pipe 31. The number of the branch pipes 32 is the same as that of the installed auxiliary distributor 251, and the number is three in the embodiment of the present disclosure. In addition, end portions of the branch pipes 32, that is, the other ends of the bypass pipe 30 are respectively connected to different auxiliary distributors 251.

In addition, in the embodiment of the present disclosure, a two way valve 33 is installed, wherein the two way valve 33 opens and closes between one end of the bypass pipe 30 and the intersection point P, that is, the bypass pipe 30 on the main pipe 31. During defrosting, the two way valve 33 is provided to receive a signal from a controller (not shown) so that the bypass pipe 30 becomes open, and high temperature gas refrigerant flows from the compressor 23 into the outdoor heat exchanger 24. Accordingly, the outdoor heat exchanger 24 may be defrosted while a heating operation is continuously performed.

In the air conditioner 100 according to the embodiment of the present disclosure, since the other ends of the bypass pipe 30 are respectively connected to the auxiliary distributors 251, the bypass pipe 30 almost may not subject to a flow path resistance of the distribution pipe 252 and may supply a high temperature gas refrigerant to the heat transfer pipe 241. Accordingly, even in the case of the big outdoor heat exchanger 24, a flow amount of the high temperature gas refrigerant is not decreased and the outdoor heat exchanger 24 may be significantly defrosted without decreasing the defrosting effect, and as a result, defrosting time while the high temperature gas refrigerant flows in the distribution pipe may be decreased compared to a conventional case, and residual frost may also be prevented during defrosting.

In addition, since the other ends of the bypass pipe 30 are respectively connected to the auxiliary distributors 251 and the number of the branch pipes 32 of the bypass pipe 30 may be decreased, a cost reduction or weight reduction can be obtained.

In addition, since the two way valve 33 is installed between one end of the bypass pipe 30 and the intersection point P, when the bypass pipe 30 is opened by the two way valve 33, the defrosting function may be implemented during a heating operation.

Even when the other ends of the bypass pipe 30 are respectively connected near the auxiliary distributors 251 between the auxiliary distributors 251 and the distribution pipes 252, the same effect can obviously be obtained.

Modified Example of First Embodiment

In addition, the present disclosure is not limited to the first embodiment.

For example, although the air conditioner 100 according to the embodiment is provided with a single outdoor heat exchanger 24, as illustrated in FIG. 3, a plurality of outdoor heat exchangers 24A and 24B may be provided. More specifically, distributors 25A and 25B, auxiliary distributors 251A and 251B, distribution pipes 252A and 252B, and bypass pipes 30A and 30B respectively corresponding to the outdoor heat exchangers 24A and 24B are installed in the air conditioner 100.

Specifically, the air conditioner 100 is provided with a first outdoor heat exchanger 24A and a second outdoor heat exchanger 24B, and a first distributor 25 a and a second distributor 25 b, and a first expansion valve 26A and a second expansion valve 26B are respectively installed to correspond to the outdoor heat exchangers 24A, 24B.

More specifically, as illustrated in FIG. 3, a first auxiliary distributor 251A and a plurality of first distribution pipes 252A are installed between the first outdoor heat exchanger 24A and the first distributor 25 a, and a second auxiliary distributor 251B and a plurality of second distribution pipes 252B are installed between the second outdoor heat exchanger 24B and the second distributor 25 b.

In addition, the auxiliary distributors 251A and 251B and the distribution pipe 252A and 252B have the same configuration as the auxiliary distributor 251 and the distribution pipe 252 of the embodiment.

In addition, as illustrated in FIG. 3, a first bypass pipe 30A and a second bypass pipe 30B are installed to respectively correspond to the outdoor heat exchangers 24A and 24B. The first bypass pipe 30A according to the modified example has the same configuration as the bypass pipe 30 of the embodiment. The second bypass pipe 30B includes a second main pipe 31B branched from a first main pipe 31A of the first bypass pipe 30A and a plurality of branch pipes 32B branched from intersection points P2 installed on the second main pipe 31B.

In addition, a first two way valve 33A is installed in the first main pipe 31A, and a second two way valve 33B is installed in the second main pipe 31B.

By the above-described configuration, even in the case of big outdoor heat exchangers 24A and 24B, frost may be significantly removed without decreasing a defrosting effect, and since when the outdoor heat exchangers 24A and 24B disposed at one side thereof is defrosted, the outdoor heat exchangers 24B and 24A disposed at the other side function as an evaporator, a decrease in heating performance during defrosting may be suppressed.

In addition, although it took thirteen minutes to defrost in a conventional configuration in which other ends of bypass pipes 30A and 30B are respectively connected between distributors 25A and 25B and expansion valves 26A and 26B, in the above-described configuration in which the other ends of bypass pipes 30A, 30B are respectively connected to the auxiliary distributors 251A, 251B, it takes five minutes, and thus defrosting time may be decreased compared to the conventional case.

In addition, although the air conditioner according to the embodiment is provided with the plurality of auxiliary distributors, the other ends of the distribution pipe may be directly connected to the heat transfer pipes without the auxiliary distributors. In this case, it is preferable that the other ends of the bypass pipes be respectively connected to the connection portions of the distribution pipe and the heat transfer pipe or to nearby.

However, the term ‘nearby’ refers to a position at a lower stream side or upper stream side from the connection portion (that is, from the connection portion toward the heat exchanger or in the opposite direction) that is separated a distance less than, for instance, one tenth of the total length of the distribution pipe.

Second Embodiment

Hereinafter, an air conditioner of a second embodiment of the present disclosure will be described in detail with reference to accompanying drawings. In addition, numerals in the second embodiment will only be used in FIGS. 4 to 9.

As illustrated in FIG. 4, an air conditioner 100 according to the embodiment of the present disclosure includes an indoor unit 10 and an outdoor unit 20 and has a heat pump cycle 200 so that a refrigerant flows in the indoor unit 10 and the outdoor unit 20.

Depressurizing units 11A and 11B connected in parallel, indoor heat exchangers 12A and 12B respectively connected to the depressurizing units 11A and 11B, and indoor blower fans 13A and 13B are installed in the indoor unit 10.

A four way valve 21, an accumulator 22, a compressor 23, an outdoor heat exchanger 24, a distributor 25, an expansion valve 26, and an outdoor blower fan 27 are installed in the outdoor unit 20.

The outdoor heat exchanger 24 includes a plurality of heat exchange units, and in the embodiment of the present disclosure, the outdoor heat exchanger 24 includes an upper heat exchange unit 241 and a lower heat exchange unit 242 which are installed in a vertical direction as illustrated in FIG. 4.

The heat exchange units 241 and 242 are connected to the distributor 25 through distribution pipes 251, and temperature sensors (not shown) are respectively installed in the heat exchange units 241 and 242.

The heat pump cycle 200 is provided with a main circuit 201 in which the depressurizing units 11A and 11B, the indoor heat exchangers 12A and 12B, the four way valve 21, the outdoor heat exchanger 24, the distributor 25, the expansion valve 26 are sequentially connected and a compression circuit 202 in which the accumulator 22 and the compressor 23 are sequentially connected and connected to the four way valve 21.

By controlling opening and closing of four ports of the four way valve 21, the heat pump cycle 200 may be provided to reverse the flow of refrigerant in the main circuit 201 and to switch a cooling operation and a heating operation. Specifically, during the cooling operation, the four way valve 21 introduces a high temperature gas refrigerant discharged from the compressor 23 to the outdoor heat exchanger 24, and during the heating operation, the four way valve 21 introduces the high temperature gas refrigerant discharged from the compressor 23 into the indoor heat exchangers 12A and 12B.

Here, a bypass pipe 30 is installed in the air conditioner 100 according to the embodiment of the present disclosure, wherein one end of the bypass pipe 30 is connected to a discharging side pipe 231 of the compressor 23, the bypass pipe 30 is branched in the middle thereof, and a plurality of the other ends thereof are simultaneously connected to distribution pipe 251. Specifically, the bypass pipe 30 includes a main pipe 31 connected to the discharging side pipe 231 of the compressor 23 and a plurality of branch pipes including a first branch pipe 321 and a second branch pipe 322 branched from the main pipe 31 and respectively connected to the distribution pipes 251.

The above-described bypass pipe 30 is provided so that a first two way valve 331 is installed in the first branch pipe 321 and a second two way valve 332 is installed in the second branch pipe 322, and when the two way valves 331 and 332 are opened, a high temperature gas refrigerant flows in the corresponding branch pipes 321 and 322. The high temperature gas refrigerant is supplied to the heat exchange units 241 and 242 through the distribution pipes 251 to which the branch pipes 321 and 322 are connected, and thus, the heat exchange units 241 and 242 are defrosted.

In addition, a defrosting controller (not shown) is installed in the air conditioner 100 according to the embodiment of the present disclosure, wherein the defrosting controller defrosts each of the heat exchange units 241 and 242 and switches the defrosted heat exchange units 241 and 242 to the upper heat exchange unit 241 and the lower heat exchange unit 242.

Specifically, the defrosting controller is provided to switch the heat exchange units 241 and 242 to be defrosted by changing each of the two way valves 331 and 332 to an open state and a closed state, and in the embodiment of the present disclosure, as illustrated in FIG. 5, before ending defrosting of one side of the heat exchange units 241 and 242 that has been started to be defrosted, the other side of the heat exchange units 242, 241 may be started.

More specifically, the defrosting controller is provided to receive a signal from a temperature sensor (not shown) installed in the upper heat exchange unit 241, and when a value of the temperature sensor is equal to or less than a predetermined first lower limit, that is, when the temperature of the upper heat exchange unit 241 is equal to or lower than the predetermined first lower temperature limit, defrosting of the upper heat exchange unit 241 starts. In addition, the defrosting controller is provided to start defrosting when the value of the temperature sensor is equal to or greater than a predetermined second lower value limit, that is, when the temperature of the upper heat exchange unit 241 is equal to or greater than the predetermined second lower temperature limit, defrosting of the lower heat exchange unit 242 starts.

In addition, in the embodiment of the present disclosure, the first lower temperature limit is set to be lower than the second lower temperature limit.

Specifically, when the temperature of the upper heat exchange unit 241 is equal to or lower than 5° below zero, the defrosting controller is set so that the first two way valve 331 becomes an open state to start defrosting the upper heat exchange unit 241, and when the temperature of the upper heat exchange unit 241 is equal to or greater than 0°, the defrosting controller is set so that the second two way valve 332 becomes an open state to start defrosting the lower heat exchange unit 242.

In addition, when values of temperature sensors (not shown) installed at heat exchange units 241 and 242 are each equal to or greater than a predetermined upper value limit, that is, temperatures of the heat exchange units 241 and 242 are each equal to or greater than the predetermined upper temperature limit, the defrosting controller is provided to complete defrosting the heat exchange units 241 and 242. Specifically, when each of the temperatures of the heat exchange units 241 and 242 is equal to or greater than 2°, the defrosting controller is set so that each of the two way valves 331 and 332 becomes a closed state to complete defrosting of the heat exchange units 241 and 242.

In addition, the upper temperature limits of the heat exchange units 241 and 242 may be freely changed without needing to be set at the same value.

With the above-described setting, as illustrated in FIG. 5, before ending defrosting of the upper heat exchange unit 241 that has been started to be defrosted, the defrosting controller starts to defrost the lower heat exchange unit 242, and the defrosting controller according to the embodiment of the present disclosure defrosts the heat exchange units 241 and 242 for approximately seven minutes and simultaneously defrosts the upper heat exchange unit 241 and the lower heat exchange unit 242 for approximately two minutes.

In addition, time taken to defrost the heat exchange units 241 and 242 may be freely changed by changing the above-described lower and upper temperature limits.

Here, each time taken to defrost the heat exchange units 241 and 242 is calculated according to a ratio between a sum of heating operation time and defrosting time versus the heating operation time, and in the embodiment of the present disclosure, the heating operation time is calculated to be equal to or greater than 80% of the sum of the heating operation time and the defrosting time. However, when frost melts within the calculated defrosting time (in the embodiment of the present disclosure, seven minutes) as described above, since the values of the temperature sensors are increased, the defrosting completes within the defrosting time.

In addition, the defrosting time (in the embodiment of the present disclosure, seven minutes) taken to defrost each of the above-described heat exchange units 241 and 242 may or may not include time (in the embodiment of the present disclosure, two minutes) taken during simultaneous defrosting of the upper heat exchange unit 241 and the lower heat exchange unit 242.

In the above-described air conditioner 100 according to the embodiment of the present disclosure, since the defrosting of the lower heat exchange unit 242 starts before ending defrosting of the upper heat exchange unit 241 that has been started to be defrosted by defrosting controller, water generated in the upper heat exchange unit 241 defrosted first is prevented from freezing in the lower heat exchange unit 242, and a degradation of heating performance of the air conditioner 100 is prevented.

In addition, since, while one side of the heat exchange units 241 and 242 is defrosted, the other side of the heat exchange units 242 and 241 is operated as an evaporator, the heat exchange units 241 and 242 may be confidently defrosted while continuing to perform a heating operation.

In addition, since the heat exchange units 241 and 242 are vertically installed and the defrosting controller sequentially switches the defrosted heat exchange units 241 and 242 to be defrosted from the upper heat exchange unit 241 positioned at upper portion toward the lower heat exchange unit 242 positioned at lower portion, water generated when the upper heat exchange unit 241 is defrosted is confidently prevented from freezing in the lower heat exchange unit 242.

Modified Example of Second Embodiment

In addition, the present disclosure is not limited to the second embodiment.

For example, although the outdoor heat exchanger 24 includes the upper heat exchange unit 241 and the lower heat exchange unit 242 in the air conditioner 100 according to the embodiment, the number of heat exchange units is not limited, and, as illustrated in an upper portion of FIG. 6 for example, the outdoor heat exchanger 24 may include an upper heat exchange unit 241, a lower heat exchange unit 242, and a middle heat exchange unit 243.

More specifically, the above-described outdoor heat exchanger 24 is provided so that the capacity of the middle heat exchange unit 243 is smaller than that of each of the upper heat exchange unit 241 and the lower heat exchange unit 242.

Specifically, the heat exchange units 241, 242, and 243 are each connected to a distributor 25 respectively through distribution pipes 251, and a first branch pipe 321, a second branch pipe 322, and a third branch pipe 323 which are a plurality of branch pipes branched from a main pipe 31 of a bypass pipe 30 are connected to the distribution pipes 251. In addition, a first two way valve 331, a second two way valve 332, and a third two way valve 333 are respectively installed in the branch pipes 321, 322, and 323.

In addition, by changing each of the two way valves 331, 332, and 333 to an open state and a closed state, the defrosting controller (not shown) is provided to switch heat exchange units 241, 242, and 243 to be defrosted. More specifically, as illustrated in a lower portion of FIG. 6, the defrosting controller is provided to start to defrost the upper heat exchange unit 241 initially, to start to defrost a middle heat exchange unit 243 before ending defrosting of the corresponding upper heat exchange unit 241, and to start to defrost the lower heat exchange unit 242 before ending defrosting of the corresponding middle heat exchange unit 243.

In addition, timings with which the defrosting controller starts and ends defrosting each of the heat exchange units 241, 242, and 243 are controlled by temperature sensors (not shown) respectively installed at the heat exchange units 241, 242, and 243 similarly to the embodiment.

According to the above-described configuration, since the capacity of the middle heat exchange unit 243 is smaller than that of each of the upper heat exchange unit 241 and the lower heat exchange unit 242, a temperature of the middle heat exchange unit 243 easily becomes high, and water generated by defrosting of the upper heat exchange unit 241 is prevented from freezing in the middle heat exchange unit 243 more confidently.

In addition, since the capacity of the middle heat exchange unit 243 is small, water generated by defrosting of the middle heat exchange unit 243 is decreased, and since an amount of the water flowing into the lower heat exchange unit 242 is small, time taken to defrost the lower heat exchange unit 242 may be decreased.

In addition, since the capacity of the middle heat exchange unit 243 is small, the capability of an evaporator is assured adequate during defrosting, and by preventing an indoor blowing temperature from being lowered, discomfort due to continued heating may be lessened.

As illustrated in FIG. 7, in the configuration including the upper heat exchange unit 241, the middle heat exchange unit 243, and the lower heat exchange unit 242, the defrosting controller may be provided to simultaneously start to defrost the upper heat exchange unit 241 and the middle heat exchange unit 243 and to simultaneously complete defrosting the lower heat exchange unit 242 and the middle heat exchange unit 243.

That is, the defrosting controller is provided to simultaneously start to defrost the upper heat exchange unit 241 and the middle heat exchange unit 243, to switch the defrosting heat exchange unit from the upper heat exchange unit 241 to the lower heat exchange unit 242 while continuing to defrost the middle heat exchange unit 243, and to simultaneously complete defrosting of the middle heat exchange unit 243 and the lower heat exchange unit 242.

Through the configuration, water generated by defrosting the upper heat exchange unit 241 is further confidently prevented from freezing in the middle heat exchange unit 243, and the heat exchange units 241, 242, and 243 may be further confidently defrosted while continuing a heating operation.

A specific configuration for implementing the above-described control may include a configuration in FIG. 8.

That is, an air conditioner 100 is further provided with auxiliary distributors 25 a to 25 c interposed respectively between distribution pipes 251 and heat transfer pipes 24 a to 24C of the heat exchange unit 241, 242, and 243, and a first branch pipe 321 and a second branch pipe 322 branched from a main pipe 31 are connected to the auxiliary distributors 25 a to 25 c.

More specifically, the first branch pipe 321 further branches off to two sides in the middle such that one side thereof is connected to the auxiliary distributor 25 a installed to correspond to the upper heat exchange unit 241 and the other side is connected to the auxiliary distributor 25 c installed to correspond to the middle heat exchange unit 243.

In addition, the second branch pipe 322 further branches off to two sides in the middle such that one side thereof is connected to the auxiliary distributor 25 b installed to correspond to the lower heat exchange unit 242 and the other side is connected to the auxiliary distributor 25 c installed to correspond to the middle heat exchange unit 243.

In addition, the first branch pipe 321 and the second branch pipe 322 are branched, are joined again to be connected to the auxiliary distributor 25 c, and check valves V1 and V2 are installed between the join point X and each of intersection points P1 and P2 installed at the branch pipe 321 and 322.

Through the above-described configuration, a high temperature gas refrigerant may be simultaneously supplied to the upper heat exchange unit 241 and the middle heat exchange unit 243 from the first branch pipe 321, and a high temperature gas refrigerant may be simultaneously supplied to the lower heat exchange unit 242 and the middle heat exchange unit 243 from the second branch pipe 322.

In addition, although in the embodiment, the defrosting controller is provided to start and complete defrosting the heat exchange unit based on values of the temperature sensors (not shown), the defrosting controller may also be provided to defrost the heat exchange units at a predetermined time based on a timer and the like as well as to overlap defrosting timings of the heat exchange units at a predetermined time.

Generally, even when the first branch pipe 321 and the second branch pipe 322 are connected near the auxiliary distributor 25 a, 25 b, and 25 c between the auxiliary distributors 25 a, 25 b, and 25 c and the distribution pipes 251, the same effect may obviously be obtained.

In addition, as illustrated in FIG. 9, an air conditioner 100 may be further provided with a heat storage tank 40 which stores heat of a compressor 23 so that a refrigerant heated by heat stored in the heat storage tank 40 flows into an outdoor heat exchanger 24 through a bypass pipe 30.

Specifically, the heat storage tank 40 is installed around the compressor 23, stores heat radiated from the compressor 23 through a contact surface with the compressor 23, and includes a heat storage medium including liquid, etc., a stored heat exchanger 41 in which a refrigerant flows and simultaneously supplies the stored heat to the refrigerant, and a stored heat temperature sensor 42 which detects a temperature of the heat storage tank (hereinafter, referred to as a stored heat temperature).

However, the heat storage tank 40 need not surely to be in contact with the compressor 23 and may be installed near the compressor 23.

More specifically, the air conditioner 100 is provided so that a refrigerant which has flown from the heat storage tank 40 flows into the outdoor heat exchange units 241 and 242 through the bypass pipe 30 after being introduced into the compressor 23. Here, as illustrated in FIG. 9, an outlet pipe 411 through which the refrigerant flows from the heat storage tank 40 is connected between the outdoor heat exchanger 24 and a four way valve 21. However, a check valve 5 is installed in the outlet pipe 411.

In addition, an inlet pipe 412 through which a refrigerant flows into the heat storage tank 40 is branched between indoor heat exchangers 12A and 12B and a distributor 25, and a third two way valve 413 which receives a signal from a controller (not shown) and is changed to an open state and a closed state is installed in the inlet pipe 412.

Hereinafter, a control related to the controller (not shown) will be described.

Here, the controller is provided to receive a signal from the stored heat temperature sensor 42 and simultaneously provided so that the third two way valve 413 becomes a closed state when the stored heat temperature is lower than a predetermined first temperature, the third two way valve 413 becomes an open state when the stored heat temperature is greater than a predetermined second temperature, and the third two way valve 413 maintains an open or closed state when the stored heat temperature is equal to or greater than the first temperature and equal to or lower than the second temperature.

That is, while the stored heat temperature is raised, the third two way valve 413 is in a closed state until the stored heat temperature reaches the second temperature, and the third two way valve 413 becomes an open state when the stored heat temperature reaches the second temperature. Meanwhile, while the stored heat temperature is lowered, the third two way valve 413 is in an open state until the stored heat temperature reaches the first temperature, and the third two way valve 413 becomes a closed state when the stored heat temperature reaches the first temperature.

In addition, the controller is provided to receive a signal from an outdoor air temperature sensor (not shown) which detects a temperature of outdoor air (hereinafter, referred to as an outdoor air temperature), when the outdoor air temperature is equal to or lower than a predetermined temperature, the third two way valve 413 becomes a closed state when the upper heat exchange unit 241 is defrosted, and the third two way valve 413 becomes an open state when the lower heat exchange unit 242 is defrosted.

Through the above-described configuration, a refrigerant may be heated by heat radiated from the compressor 23, and a high efficiency defrosting operation may be performed. Accordingly, a degradation of heating performance during the defrosting operation may be prevented, and a user's comfort may be maintained during the defrosting operation.

In addition, heat of the heat storage tank 40 may be intensively used during latter half of the defrosting operation, and simultaneously the capacity of the heat storing medium and the size of the heat storage tank 40 may be diminished, the outdoor unit 20 may be compactly formed, and cost is reduced.

In addition, since a refrigerant which has been heated by the heat storage tank 40 flows into the heat exchange units 241 and 242 after being introduced to the compressor 23, the refrigerant temperature may become even higher, and defrosting time of each of the heat exchange units 241 and 242 may be decreased.

In addition, the present disclosure is not limited to the above-described embodiments and may obviously be variously modified without departing from the purpose of the present disclosure. 

1. An air conditioner comprising: a refrigerant circuit provided so that a compressor, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger are connected; a distributor provided between the outdoor heat exchanger and the expansion valve; a plurality of distribution pipes provided to be connected to a plurality of heat transfer pipes in which each one end thereof is connected to the distributor and the other end thereof is provided in the outdoor heat exchanger; and a bypass pipe having one end connected to the compressor and configured to branch off to form a plurality of the other ends, wherein the plurality of the other ends are provided to be respectively connected between the plurality of distribution pipes and the plurality of heat transfer pipes.
 2. The air conditioner of claim 1, further comprising a plurality of auxiliary distributors to which the plurality of heat transfer pipes are connected, wherein each of the other ends of the plurality of distribution pipes are respectively connected to the plurality of heat transfer pipes through the auxiliary distributors, and the other ends of the bypass pipe are respectively provided to be connected to the plurality of auxiliary distributors.
 3. The air conditioner of claim 1, wherein the outdoor heat exchanger is installed in plurality, and the distributor, the distribution pipe, and the bypass pipe are provided in plurality to correspond to the plurality of heat exchangers.
 4. The air conditioner of claim 1, wherein: the outdoor heat exchanger includes a plurality of heat exchange units which are classified by the connections to the plurality of heat transfer pipes; the air conditioner further includes a defrosting controller provided to individually remove frost generated in the plurality of heat exchange units by each of the plurality of heat exchange units; and the defrosting controller starts to defrost one heat exchange unit, and starts to defrost another heat exchange unit before ending defrosting the one heat exchange unit.
 5. The air conditioner of claim 4, wherein the plurality of heat exchange units are provided to be vertically disposed, and the defrosting controller is provided so that defrosting is sequentially performed from the one heat exchange unit which is positioned at an upper side to the another heat exchange unit positioned at a lower side.
 6. The air conditioner of claim 4, wherein the outdoor heat exchangers include an upper heat exchange unit, a middle heat exchange unit, and a lower heat exchange unit, and a capacity of the middle heat exchange unit is smaller than that of each of the upper heat exchange unit and the lower heat exchange unit.
 7. The air conditioner of claim 6, wherein the defrosting controller is provided to cause the upper heat exchange unit and the middle heat exchange unit to be defrosted simultaneously, to switch to defrosting the lower heat exchange unit when the upper heat exchange unit is completely defrosted, and to cause the middle heat exchange unit and the lower heat exchange unit to be defrosted simultaneously.
 8. The air conditioner of claim 6, wherein the defrosting controller is provided so that the middle heat exchange unit starts to defrost between start and end of defrosting of the upper heat exchange unit and the middle heat exchange unit ends defrosting between start and end of defrosting of the lower heat exchange.
 9. The air conditioner of claim 1, further comprising a heat storage tank which stores heat of the compressor, wherein a refrigerant heated by heat stored in the heat storage tank is provided to be introduced into the outdoor heat exchanger through the bypass pipe.
 10. The air conditioner of claim 9, wherein the refrigerant discharged from the heat storage tank flows into the outdoor heat exchanger through the bypass pipe after being introduced into the compressor.
 11. An air conditioner comprising: a refrigerant circuit provided so that a compressor, an outdoor heat exchanger including a plurality of distinct heat exchange units, an expansion valve, and an indoor heat exchanger are connected; a distributor provided between the outdoor heat exchanger and the expansion valve; and a bypass pipe provided so that one end is connected to the compressor and the other end is connected between the distributor and the outdoor heat exchanger, wherein the plurality of heat exchange units are each connected to the bypass pipe and individually defrosted by a time difference.
 12. The air conditioner of claim 11, wherein the plurality of heat exchange units are vertically disposed in the outdoor heat exchanger, and defrosting is sequentially performed from the heat exchange unit positioned at an upper side to the heat exchange unit positioned at a lower side.
 13. The air conditioner of claim 12, wherein the number of the plurality of heat exchange units are provided equal to or more than three, and the one heat exchange unit disposed between the heat exchange units has a capacity smaller than that of each of the other plurality of heat exchange units disposed at the upper and lower sides of the outdoor heat exchanger.
 14. The air conditioner of claim 12, wherein the bypass pipe includes a plurality of branch pipes formed by a part of the bypass pipe being branched so that the bypass pipe is connected between the plurality of heat exchange units and the distributor, and each of the plurality of branch pipes is provided with a two way valve.
 15. The air conditioner of claim 14, wherein the two way valves are individually opened or closed according to defrosting times of the plurality of heat exchange units.
 16. The air conditioner of claim 14, further comprising a plurality of auxiliary distributors provided between a plurality of heat transfer pipes provided in the plurality of heat exchange units and the distributor, wherein the plurality of branch pipes are respectively connected to the plurality of auxiliary distributors.
 17. The air conditioner of claim 11, wherein the outdoor heat exchanger is installed in plurality, and the distributor and the bypass pipe are provided in plurality to correspond to the plurality of heat exchangers.
 18. The air conditioner of claim 11, further comprising a heat storage tank which stores heat of the compressor, wherein a refrigerant heated by heat stored in the heat storage tank is provided to be introduced into the plurality of heat exchange units through the bypass pipe.
 19. The air conditioner of claim 18, wherein the refrigerant discharged from the heat storage tank is provided to flow into the plurality of heat exchange units through the bypass pipe after being introduced into the compressor.
 20. An air conditioner comprising: a refrigerant circuit provided so that a compressor, an outdoor heat exchanger including a plurality of heat exchange units, an expansion valve, and an indoor heat exchanger are connected; a distributor provided between the plurality of heat exchange units and the expansion valve; and a bypass pipe provided so that one end is connected to the compressor and the other end is connected between the distributor and the plurality of heat exchange units, wherein one end of the bypass pipe branches off in plurality and is connected to the plurality of heat exchange units, and a refrigerant discharged from the compressor is individually supplied to the plurality of heat exchange units through a plurality of two way valves provided in the bypass pipe so that frost generated in the plurality of heat exchange units is individually removed. 